package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经登录
 */
@Slf4j
@WebFilter(filterName = "loginCheckLogin",urlPatterns = "/*")
public class LoginCheckFilter implements Filter {

    //路径匹配器
    private static final AntPathMatcher ANT_PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        //获取本次请求的uri
        String requestURI = request.getRequestURI();

        log.info("拦截到请求: {}",requestURI);

        //不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/user/sendMsg",
                "/user/login"
        };//   /*一层目录任意  /**多层目录任意   这里的通配符是由AntPathMatcher解析


        //判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        if (check){
            //不需要处理直接放行
            log.info("本次请求{}无需处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

        //判断登录状态，如果已经登陆，直接放行
        if(request.getSession().getAttribute("employee") != null){
            //获取id,存入ThreadLocal
            Long id = (Long) request.getSession().getAttribute("employee");
            BaseContext.setCurrentId(id);

            log.info("用户已登陆");
            filterChain.doFilter(request,response);
            return;
        }

        //判断移动端用户是否已经登录
        if(request.getSession().getAttribute("user") != null){
            //获取id,存入ThreadLocal
            Long id = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(id);

            log.info("用户已登陆");
            filterChain.doFilter(request,response);
            return;
        }

        //未登录返回未登录结果，通过输出流方式向页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls,String requestURI){

        for (String url : urls) {
            boolean match = ANT_PATH_MATCHER.match(url, requestURI);
            if (match){
                return true;
            }
        }
        return false;
    }


}
